Nick:
I just finished the first phase of a large project for the state of
California using a quad stack. The generators are three phase but the
campus is all split phase. They were able to center tap one winding of the
generators and use the two phases on either side. I was skeptical,
thinking that the phase angle would be 120 degrees, not 180 degrees as
required for the quad stack, but an oscilloscope proved the 180 degree
phase angle. The quad stack is happy with the two phases of the three
phase. Let me repeat that this is only possible because the winding on the
generator between the two phases we are using was center tapped and bonded
to create a neutral.
I was told that many large three phase generators have a 12 winding
configuration. I belive that this configuration will allow the center tap
to be made. You should verify this will not void any warranties or damage
the generator.
The down side is that there is some loss of generator capacity, but it was
far less than I predicted, somewhere about 80% of name plate.
I have pictures of the PV and inverters on our web site, but not of the
generators. I think they are 30 KVA Kohlers. As a side note, the
generator system is very unique. There are three generators and they can
run one, two or three in synchronization, as needed. Also, the inverter
system does not through-put power. The generator control system switches
the generators off the main buss moments before switching the inverters
onto the main buss. To further complicate things, the generators must be
loaded at close to capacity at all times to reduce emissions. There is a
load bank that switches in and out to accomplish this. It took Kohler
Corporate many trips to get this working, and I'm not sure I really belive
they have all of the bugs out yet.
Good Luck,
William Miller
At 09:03 PM 1/14/2009, you wrote:
Hi Nick,
Why you want the change from single to 3 phase?
Pretty big difference that.
jay
peltz power
On Jan 14, 2009, at 4:56 PM, Nick Houser wrote:
Has anybody done (or even TRIED) this? The Quad stack is exactly
like page 20 of the manual. Owner
refuses to let me convert the Quad panel to three phase as he won't
give up the forth inverter' contribution.
Ditto repacing or converting the generator. Related question: If
the transformer is a viable option, how do
I size it? Help. please, I'm running out of options. Nick Houser,
Off Grid Services, Powell River, BC
[email protected] 604-483-4898 Fell free to contact me off
list, and Happy New Year. ALL!!!!!
--
Using Opera's revolutionary e-mail client: http://www.opera.com/mail/
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
